Interlocking container and cover arrangement



Feb. 12, 1963 INTERLOCKING CONTAINER AND COVER ARRANGEMENT Filed April 3, 1961 Irv/6722 57 Frank li f'laqgzzh F. MOLAUGHLIN 3,077,284 r United States Patent 3,677,284 INTERLGCKING @GNTAHNER AND COVER ARRANGEMENT Frank L. McLaughlin, Qhicago, IlL, assignor to Container Corporation of America, Chicago, Ill., a corporation of Delaware Filed Apr. 3, 1961, Sel No. 100,135 (Ilaims. (Cl. 220-450 This invention relates to containers, and moreparticularly to an improved self-seaiingleak-proof container with an interlocking cover.

The invention comprehends a reusable container of the type commonly employed in the packaging of frozen foods, which is formed of resilient or flexible plastic material such as polyethylene, polystyrene, or polypropylene.

Although leak-proof sealing between arcuate containers and covers has been accomplished in the past, greater problems have been presented in the case of square or rectangular containers and covers.

A primary object of the invention is the provision of a container and cover arrangement having an improved self-sealing, leak-proof, interlocking relation between the container and cover.

A more specific object of the invention is to provide, in a container and cover arrangement of the type described, a 'non-arcuate container with a flanged side wall lip receivable within a peripheral groove of a cover rim and having a camming surface thereon engageable with a cooperating surface on the cover to facilitate entry of the container lip into the cover rim groove.

These and other objects of the invention will be apparent from an examination of the following description and drawings, wherein:

FIGURE 1 is a perspective view of a container embodying features of the invention, with the cover removed;

FIGURE 2 is a vertical section taken on line 22 of FIGURE 1;

FIGURE 3 is a side elevation, with portions shown in vertical section, of a container cover embodying features of the invention;

FIGURE 4 is an enlarged vertical section of a portion of the container of FIGURE 1;

FIGURE 5 is an enlarged vertical section of a portion of the cover of FIGURE 3; and

FIGURE 6 is a composite of the views errrouaas 4'and 5, showing the relationship of the container to the cover.

Referring now to the drawings for a better understand ing of the invention, and particularly to FIGURE 1 and FIGURE 3, it will be seen that a container embodying features of the invention, and indicated generally at 143, comprises a bottom wall'liZ having upstanding from the side edges thereof a plurality of integrally formed generally vertically disposed side walls 14.

The bottom wall 12 is preferably rectangular in shape with a raised dome-like center portion 16 which serves to prevent conveyer burns from occurring when ice cream or similar frozen items are packed in the container. The dome also has the added function of increasing the freezing speed of the contents of the container by providing for a more uniform distribution of the contents. Like- 'wise the dome facilitates heating of the contents when ice 2 it is desired to serve them hot directly from the container.

Each of these side walls 14 of the container may be provided with a generallyvertically extending internal rib it These ribs provide air channels when the flexible walls of the container are flexed outwardly to permit atmospheric air to fiow down along the channel and pass below the contents of the container to overcome the vacuum which would ordinarily be created between the contents of the container and the bottom wall of the container.

In orderto faciliate stacking of the containers there may be provided at the upper portions of the corners between adjacentside walls outwardly extending stacking lugs 20 which present generally horizontally extending downwardly facing stacking surfaces 22.

As best seen in FIGURE 4, each of the sidewalls of the container present a pair of inner and outer sidewalls surfaces 24 and 26, respectively, which diverge upwardly toward their upper extremities where they inerge'into a peripheral lip 28. Still referring to FIGURE 4, it will be seen that the lip 28 projects outwardly from the sidewall 14 and is generally semi-cylindrical in cross'sectiornpresenting an upwardly facing semi-cylindrical convex cam surface 36 and a generally horizontal downwardlyfacing flat sealing surface 32 which extends from theupper extremity of the side wall outer surface 26 to the outer extremity of the camrning surface 32. The purpose of the particularstructure of the side wall lip 2tiwill be described later in the specification in connection with the cover.

As thus seen in FIGURES 3 and 5, the cover or lid indicated generally atdtl, comprises a generally rectangular relatively thinflat topwall panel 42 having at its outer periphery a grooved rim 44. The rim 44 includes a pair of generally parallel horizontally spaced inner and outer rim walls 46' and 48, respectively, interconnected at their upper edges by anintegralgenerally horizontally extending top wall 5dwhich defines with the inner and outer walls a main or primary lip receiving opening '52. At its lower portion outer wall 43 is enlarged to provide an inwardly projecting shelf 5'4 having an inwardly facing camming surface 56 which slopes upwardly and inwardly toward the center of the cover, and also having a generally fiat upwardly facing horizontal sealing surface 58 which extends outwardly from the upper extremity of carnming surface 56. The sealing surface '53 of the cover rim is disposed parallel to and spaced vertically below the downwardly facing inner surface 60 of the rim top wall to define therewith a peripheral groove 62 adapted to receive lip 28 of the cover side wall 14-. V

In applying the cover to the container to elfect a leakpr'oof seal therebetween, the cover rim isplaced over the container'lip so that as the cover is lowered onto the container the rounded camming surface 3% of the container side wall lip 28 will engage and ride up the cam surface 56 on the cover rim shelf until such time'asth'e sealing surface 32 of the lip is level with the sealing surface 53 of the rim. At this point theside walls of the container which have been flexed inwardly by the inward upward sloping of the cam surfaces 56 of the cover rim will automatically flex outwardly tothe closed interlocking self-sealing leak-proof position shown in FIGURE 6 as the container lip enters the cover groove with the cam surface 30 of the container lip being in tangential abutting relationship with the inner surface so of the cover rim top wall and the downwardly facing sealing surface 32 of the container side wall lip disposed in full face abutting engagement on the upwardly facing sealing surface 58 of the cover rim shelf.

In order to remove the cover, one corner is lifted and the cover is peeled back off the container.

I claim:

1. A leak-proof, self-sealing, inter-locking containercover arrangement for a multi-sided container and cover formed of a flexible material: comprising an open-top container member having a bottom wall and a plurality of side walls upstanding therefrom presenting at their upper edges a continuous peripheral lip, each of said side walls having a pair of spaced inner and outer surfaces, said lip being formed integrally with the upper extremity of each side wall and being generally semi-cylindrical in vertical cross section and presenting a flat downwardly facing sealing surface extending horizontally outward from the upper extremity of the side wall outer surface and presenting an arcuate upwardly facing cam surface extending from the upper extremity of the side wall inner surface to the outer extremity of said sealing surface; and a generally flat cover member having a center plate with an integrally formed peripheral rim adapted to seat on said container member lip in interlocking engagement therewith, said rim including a pair of parallel inner and outer vertical walls spaced from each other and interconnected at their upper edges by a horizontal top wall, said outer wall having adjacent its lower extremity a shelf extending toward said inner wall presenting a generally flat upwardly facing sealing surface spaced from said top wall to define with said top wall and an upper portion of said outer wall a lip receiving groove and presenting an inwardly facing cam surface sloping inwardly and upwardly to the inner extremity of said rim sealing surface; said lip cam surface being adapted to ride up said rim cam surface, as the cover is urged downwardly onto the container, and flex one of said members relative to the other member until said lip is received within said groove with the respective sealing surfaces in full face abutting engagement with each other.

2. A leak-proof, self-sealing, inter-locking containercover arrangement for a multi-sided container and cover formed of a flexible material: comprising an open-top container having a bottom wall and a plurality of side walls upstanding therefrom presenting at their upper edge a continuous peripheral lip, each of said side walls having a pair of spaced inner and outer surfaces, said lip being formed integrally with the upper extremity of each side wall and being generally semi-cylindrical in vertical cross section and presenting a flat downwardly facing sealing surface extending horizontally outward from the upper extremity of the side wall outer surface and presenting an arcuate upwardly facing cam surface extending from the upper extremity of the side wall inner surface to the outer extremity of said sealing surface; and a generally flat cover having a center plate with an integrally formed peripheral rim adapted to seat on said container lip in interlocking engagement therewith, said rim including a pair of parallel inner and outer vertical walls spaced from each other and interconnected at their upper edges by a horizontal top wall, said outer wall having adjacent its lower extremity a shelf extending toward said inner wall presenting a generally flat upwardly facing sealing surface spaced from said top wall to define with said top wall and an upper portion of said outer wall a lip receiving groove and presenting an inwardly facing cam surface sloping inwardly and upwardly to the inner extremity of said rim sealing surface; said lip cam surface being adapted to ride up said rim cam surface, as the cover is urged downwardly onto the container, until said lip is received within said groove with the respective sealing surfaces in full face abutting engagement with each other.

3. A leak-proof, self-sealing, inter-locking containercover arrangement for a multi-sided container and cover formed of a flexible material: comprising an open-top container having a bottom wall and a plurality of side walls upstanding therefrom presenting at their upper edges a continuous peripheral lip, each of said side walls having a pair of spaced inner and outer surfaces, said lip being formed integrally with the upper extremity of each side wall and being generally semi-cylindrical in vertical cross section and presenting a fiat downwardly facing sealing surface extending horizontally outward from the upper extremity of the side wall outer surface and presenting an arcuate upwardly facing cam surface extending from the upper extremity of the side wall inner surface to the outer extremity of said sealing surface; and a cover having a peripheral rim adapted to seat on said container lip in interlocking engagement therewith, said rim including a pair of parallel inner and outer vertical walls spaced from each other and interconnected at thier upper edges by a horizontal top wall, said outer wall having adjacent its lower extremity a shelf extending toward said inner wall presenting a generally flat upwardly facing sealing surface spaced from said top wall to define with said top wall and an upper portion of said outer wall a lip receiving groove and presenting an inwardly facing cam surface sloping inwardly and upwardly to the inner extremity of said rim. sealing surface; said lip cam surface being adapted to ride up said rim cam surface, as the cover is urged downwardly onto the container, until said lip is received within said groove with the respective sealing surfaces in full face abutting engagement with each other.

4. A leak-proof, self-sealing, inter-locking containercover arrangement for a multi-sided container and cover formed of a flexible material: comprising an open-top container having a bottom wall and a plurality of side walls upstanding therefrom presenting at their upper edges a continuous peripheral lip, each of said side walls having a pair of spaced inner and outer surfaces, said lip being formed integrally with the upper extremity of each side wall and being generally semi-cylindrical in vertical cross section and presenting a flat downwardly facing sealing surface extending horizontally outward from the upper extremity of the side wall outer surface and presenting an arcuate upwardly facing cam surface extending from the upper extremity of the side wall inner surface to the outer extremity of said sealing surface; and a cover having a peripheral rim adapted to seat on said container lip in interlocking engagement therewith, said rim including a generally horizontal top wall and a generally vertical outer Wall depending from the outer edge of said top wall, said outer wall having adjacent its lower extremity an inwardly projecting shelf presenting a generally flat upwardly facing sealing surface spaced from said top wall to define with said top wall and upper portion of said outer wall a lip receiving groove and presenting an inwardly facing cam surface sloping inwardly and upwardly to the inner extremity of said rim sealing surface; said lip cam surface being adapted to ride up said rim cam surface, as the cover is urged downwardly onto the container, until said lip is received within said groove with the respective sealing surfaces in full face abutting engagement with each other.

5. A leap-proof, self-sealing, inter-locking containercover arrangement for a multi-sided container and cover formed of a flexible material: comprising an open-top container having a bottom wall and a plurality of side walls upstanding therefrom presenting at their upper edges a continuous peripheral lip, each of said side walls having a pair of spaced inner and outer surfaces, said lip being formed integrally with the upper extremity of each side wall and presenting an upwardly and outwardly facing curved cam surface and a flat sealing surface extending inwardly from the lower extremity of said cam surface to the outer surface of said side wall; and a cover having a peripheral rim adapted to seat on said container lip in interlocking engagement therewith, said rim including a generally horizontal top wall and a generally vertical outer enemas 5 wall depending from the outer edge of said top wall said outer wall having adjacent its lower extremity an inwardly projecting shelf presenting a. generally flat upwardly facing sealing surface spaced frcm said top Wall to define with said top wall and upper portion of said outer wall a lip receiving groove and presenting an inwardly facing cam surface sloping inwardly and upwardly to the inner extremity of said rim sealing surface; said lip cam surface being adapted to ride up said rim cam surface, as the cover is urged downwardly onto the container, until said lip is received within said groove with the respective sealing surfaces in full face abutting engagement with each other.

References Cited in the file of this patent UNITED STATES PATENTS FOREIGN PATENTS France Apr. 19, 1960 

1. A LEAK-PROOF, SELF-SEALING, INTER-LOCKING CONTAINERCOVER ARRANGEMENT FOR A MULTI-SIDED CONTAINER AND COVER FORMED OF A FLEXIBLE MATERIAL: COMPRISING AN OPEN-TOP CONTAINER MEMBER HAVING A BOTTOM WALL AND A PLURALITY OF SIDE WALLS UPSTANDING THEREFROM PRESENTING AT THEIR UPPER EDGES A CONTINUOUS PERIPHERAL LIP, EACH OF SAID SIDE WALLS HAVING A PAIR OF SPACED INNER AND OUTER SURFACES, SAID LIP BEING FORMED INTEGRALLY WITH THE UPPER EXTREMITY OF EACH SIDE WALL AND BEING GENERALLY SEMI-CYLINDRICAL IN VERTICAL CROSS SECTION AND PRESENTING A FLAT DOWNWARDLY FACING SEALING SURFACE EXTENDING HORIZONTALLY OUTWARD FROM THE UPPER EXTREMITY OF THE SIDE WALL OUTER SURFACE AND PRESENTING AN ARCUATE UPWARDLY FACING CAM SURFACE EXTENDING FROM THE UPPER EXTREMITY OF THE SIDE WALL INNER SURFACE TO THE OUTER EXTREMITY OF SAID SEALING SURFACE; AND A GENERALLY FLAT COVER MEMBER HAVING A CENTER PLATE WITH AN INTEGRALLY FORMED PERIPHERAL RIM ADAPTED TO SEAT ON SAID CONTAINER MEMBER LIP IN INTERLOCKING ENGAGEMENT THEREWITH, SAID RIM INCLUDING A PAIR OF PARALLEL INNER AND OUTER VERTICAL WALLS SPACED FROM EACH OTHER AND INTERCONNECTED AT THEIR UPPER EDGES BY A HORIZONTAL TOP WALL, SAID OUTER WALL HAVING ADJACENT ITS LOWER EXTREMITY A SHELF EXTENDING TOWARD SAID INNER WALL PRESENTING A GENERALLY FLAT UPWARDLY FACING SEALING SURFACE SPACED FROM SAID TOP WALL TO DEFINE WITH SAID TOP WALL AND AN UPPER PORTION OF SAID OUTER WALL A LIP RECEIVING GROOVE AND PRESENTING AN INWARDLY FACING CAM SURFACE SLOPING INWARDLY AND UPWARDLY TO THE INNER EXTREMITY OF SAID RIM SEALING SURFACE; SAID LIP CAM SURFACE BEING ADAPTED TO RIDE UP SAID RIM CAM SURFACE, AS THE COVER IS URGED DOWNWARDLY ONTO THE CONTAINER, AND FLEX ONE OF SAID MEMBERS RELATIVE TO THE OTHER MEMBER UNTIL SAID LIP IS RECEIVED WITHIN SAID GROOVE WITH THE RESPECTIVE SEALING SURFACES IN FULL FACE ABUTTING ENGAGEMENT WITH EACH OTHER. 